Gottwald Alexander, Kaser Hendrik, Kolbe Michael
Physikalisch-Technische Bundesanstalt, Abbestraße 2-12, Berlin 10587, Germany.
J Synchrotron Radiat. 2019 Mar 1;26(Pt 2):535-542. doi: 10.1107/S1600577518018428. Epub 2019 Feb 6.
At the Metrology Light Source, an electron storage ring dedicated to metrological applications, the U125 insertion device beamline utilizes undulator radiation for various applications over a broad spectral range. Using a hybrid normal-incidence and grazing-incidence in-vacuum switchable plane-grating monochromator, a spectral region ranging from the near-infrared to soft X-ray is covered. The beamline is dedicated to surface-analytical methods, e.g. ellipsometry, photoelectron spectroscopy or photoemission tomography. The traceability of radiometric quantities, i.e. quantitative determination of the available radiant power (or photon flux), is required for some of these applications to support the metrological aspect of the measurements. In particular, attention is paid to the suppression of unwanted spectral contributions from higher diffraction orders, and to the monitoring of the radiation intensity during the measurements. With the results from the beamline commissioning, an uncertainty budget for all relevant radiometric quantities was established.
在计量光源（一个专门用于计量应用的电子储存环）中，U125插入式装置光束线利用波荡器辐射在很宽的光谱范围内进行各种应用。使用一种混合的垂直入射和掠入射真空可切换平面光栅单色仪，覆盖了从近红外到软X射线的光谱区域。该光束线专门用于表面分析方法，例如椭圆偏振测量、光电子能谱或光发射断层扫描。对于其中一些应用，为了支持测量的计量学方面，需要辐射量的可追溯性，即对可用辐射功率（或光子通量）进行定量测定。特别要注意抑制来自更高衍射级的不需要的光谱贡献，以及在测量过程中监测辐射强度。根据光束线调试的结果，建立了所有相关辐射量的不确定度预算。
